Grinding, polishing, and featheredging tool



April 6, 1954 c. P. RHEES GRINDING, POLISHING, AND FEATHEREDGING TOOLFiled Oct. 6, 1952 INVENTOR. C IPM R RHELS.

ATTORNfY.

Patented Apr. 6, 1954 GRINDING, POLISHING, AND FEATHEREDGING TOOL CarmP. Rhees, Staten Island, N. Y.

Application October 6, 1952, Serial No. 313,211

3 Claims. (01. 51-197 This invention relates to a grinding, polishing,and feather-edging tool, and it constitutes an improvement over theinvention which is disclosed and claimed in Patent No. 2,567,782, whichwas issued to me on September 11, 1951.

The tool which constitutes the subject matter hereof possesses all ofthe features and advantages of the tool which is disclosed and claimedin my said patent, and it performs all of the functions which saidpatented tool is capable of performing. The difierences between the twotools reside in the locking means for holding the grinding, polishingand feather-edging discs in place. The present locking means constitutesa substantial and important advance over the locking means disclosed andclaimed in said patent and over all prior forms of locking means knownto the prior art.

It is the principal object of this invention to provide a locking meansfor tools of the character described, which is adjustable to thethickness of the working disc and its supporting pad or backing, whichpossesses a tensionally engaged, positive locking element, and which isreadily unlocked to replace one working disc with another.

The locking means includes an annular flange which engages the workingsurface of the working disc and holds it flat against the pad orbacking. This annular flange is provided with i a centrally disposedrecessed portion or well which performs several important functions.First of all, it encloses a good part of the locking mechanism so as toprevent it from projecting outwardly beyond the working plane of theworking disc. In the second place, this recessed portion serves as acentering device to center the working disc on the pad or backing. Inthe third place, it serves as a vehicle for carrying some of the movingparts of the locking mechanism and for transmitting their clampingaction through the annular flange to the working disc.

The locking means also includes a springurged stud which projectsthrough the recessed portion of the annular flange. The spring meansacts against said recessed portion and against a button on the outsideof said stud to urge said stud axially outwardly. On the opposite orinner end of the stud is a shoulder which is engageable with a secondlocking eled ment to lock the stud, and with it the recessed annularflange and the working disc in place on the tool. The second lockingelement last mentioned is on the tool itself and the interaction betweensaid second locking element and the shoulder is very simple: when theshoulder is behind the second locking element, the locking mechanism isin locked condition; when the shoulder is in front of the second lockingelement, the locking mechanism is unlocked. The tension member abovementioned is the means of holding the shoulder in engagement with thesecond locking element when the shoulder is situated behind said secondlocking element.

The invention is illustrated in the accompanying drawing, in which:

Fig. 1 is a back view of the operating head of a tool made in accordancewith this invention.

Fig. 2 is a front view thereof, showing a sanding disc clamped thereon.

Fig. 3 is a back view of said operating head with the working disc andpad or backing removed therefrom.

Fig. 4 is a side view of the operating head as shown in Fig. 3.

Fig. 5 is a front or inside view of said operating head, with theworking disc and pad or backing removed therefrom to expose the lockingmember which engages the shoulder of the locking stud to lock theworking disc in place.

Fi 6 is a back view of the recessed annular flange which clamps theworking disc in place.

Fig. 7 is a side view, partly broken away and in section, of saidrecessed annular flange.

Fig. 8 is a side view of the locking stud of the locking mechanism.

Fig. 9 is an end view thereof.

Fig. 10 is a section through a tool made in accordance with thisinvention, showing the locking mechanism in locked position and show-=ing a working disc clamped to the pad or backing.

Fig. 11 is a fragmentary view showing another type of resilient pad orbacking which may be mounted on the tool herein described and claimed.

Fig. 12 is a sectional view on the line I2-l2 of Fig. 11.

Fig. 13 is a view similar to Fig. 8 but showing a modification.

The grinding, polishing and feather-edging tool which is herein claimedincludes an internally threaded tubular fitting 2!] which may be securedto the driving shaft of the tool in conventional manner. Secured to saidtubular fitting, as by welding, is a deeply recessed disc 22. Secured tosaid recessed disc 22 is a second disc 24. This second disc may be madeof stamped sheetmetal and so may the recessed disc and the two may bespot-welded together, and constitute a bracket. It may be desired,

however, to make disc 24 out of a more flexible material, such as sheetplastics of the Micarta type of Westinghouse Electric Corporation orFormica of the Formica Insulation Company. In such case, disc 24 wouldbe riveted or otherwise secured to the recessed disc 22. Cemented orotherwise secured to disc 24 is a pad or backing 26 which serves as aback support for working disc 28-. This working disc may be of anyconventional type, it may be an abrasive disc for sanding purposes or arubber disc for polishing purposes or any other type of working discwhich is conventionally used in connection with tools of this generalcharacter.

Figs. 11 and 12 illustrate the use of a rubber disc or backing 30 whichmay be substituted for the pad or backing 26. This disc is provided witha plurality of pointed projections 32 which are molded thereon,integrally therewith and furnishes a very resilient backing for workingdisc 28.

It will be noted in Figs. and that recessed disc 22 serves as acup toaccommodate a leaf spring 35. The inner end 34a. of said leaf spring iscurled partly around tubular fitting 29. The spring is then bent twiceto form a pair of oppositely disposed bights 3d?) and 340 respectively.The opposite end 34d then extends through an opening 36 in the side oftubular fitting 28, and it then projects outwardly from said recessed orcupped disc 22 through an opening 38 formed in its side wall. Theportion of the spring which extends into opening in the tubular fitting2t is biased or twisted to provide an angular or sloping portion 34c.This sloping portion participates in a camming action which willhereinafter be described, and it also presents a sharp locking edge forengagement with the locking shoulder which will also hereinafter bedescribed.

The face plate which holds the working disc in place against the pad orbacking is a deeply recessed or cupped disc 40 which comprises anannular flange portion 42 and a cup dd which is disposed centrallythereof. A central opening fit is formed in said cup portion 4 5'. Itwill be noted in Fig. 10' that padding 26 is provided with a relativelylarge hole 48 formed centrally thereof. A corresponding hole 59 isformed in disc 24. It will be noted that cup portion M projects intoboth holes 48 and 58 and, of course, through a corresponding hole whichis formed in the working disc. Annular flange d2 abuts the face orWorking surface of the working disc and it holds said working disc inplace against the pad or backing 26.

A. locking stud 52 is provided for inter-engaging the cupped disc 49with locking element 34. This stud has a stem or shank portion 5d, ashoulder portion 55 at one end and a fiat disc or button portion 58 atthe opposite end. Shank 54 extends through hole $6 in the cupped disc46. A compression spring 60 is coiled about shank 5d and one end of itabuts disc 58 and the opposite end abuts cup portion 44 of cupped disc48. The spring acts upon the locking stud to push it outwardly, that is,leftwardly as viewed in Fig. 10. It may be pushed manually inwardly byfinger pressure against the button or disc end 58.

The shoulder portion 56 may be an anti-friction roller 55a. having itsinner race 562) secured to reduced end 54a of the stem, as seen in Fig.13.

It will be noted in Fig. 10 that shoulder portion5'5 of locking stud 52is engageable with the inner edge (right edge as viewed in Fig. 10) ofslopingv portion 34a of locking spring 34-. When the locking stud isinserted into the outer end (left end as viewed in Fig. 10) of thetubular fitting 20, its shoulder portion 56 cams the sloping portion Meof locking spring 34 out of its way so that it can reach its innerposition in tubular fitting 20 as shown in Fig. 10. Once shoulderportion 56 clears the sloping portion 34c of the locking spring, saidsloping portion springs back and locks behind said shoulder portion,thereby preventing disl'odgment of said locking stud.

Spring tension is now provided between button end 58 of the locking studand cup portion 44 of the recessed disc 40. Said recessed disc is urgedinwardly (rightwardly as viewed in Fig. 10) and the locking stud isurged outwardly (leftwardly as viewed in Fig. 10). Consequently, flangeportion 42 of recessed disc 40 bears against the face of the workingdisc 28 and the shoulder portion 56 bears against the locking spring 34.The effect is to clamp the working disc 28 against pad 26 and to lockshoulder portion 58 against the inner edge (right edge as viewed in Fig.10) of the: sloping portion E ie of the locking spring. It will beunderstood that the resilience of spring 60 will compensate or adjustfor varying thicknesses in the working disc 28 and pad 26 so that thesame clamping action will be had despite such variations.

To free the working disc 28 from the tool which is hereinabovedescribed, all that need be done is to disengage the lockin stud 52 fromthe locking spring 3 3. This may be done by manually moving theoutwardly projecting end 35d of said looking spring in counterclockwisedirection as viewed in Fig. 5 so as to disengage the sloping portion 34cof said spring from shoulder portion 56 of the locking stud.

The foregoing is illustrative of a preferred form of this invention, andit will clearly be understood that this preferred form may be modifiedand other forms may be provided within the broad spirit of the inventionand the broad scope of the claims.

Havin thus described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. A grinding, polishing and feather-edging tool comprising a tubularfitting which is attachable to a drive shaft, a bracket on said tubularfit-- ting, a backing on said bracket, said backing having a holeaxially aligned with said tubular fitting, a cupped disc having a centercup portion and an annular flange portion which extends outwardly fromsaid cup portion, said cup portion being disposed within the hole in thebacking, said flange portion being disposed against only said backing toclamp a working disc against said backing only, said cup portion havinga holeformed therein in concentric relation to the hole in the backing,a locking stud projecting through the hole in the cup portion and thehole' in the backin and into said tubular fitting, a button portion onthe outer end of said locking stud, a compression spring between saidbutton and said cup portion to urge said stud outwardly and the cuppeddisc inwardly and against said backing, a locking member on the innerend of said stud and a second locking member on said tubular fitting,said locking members being interengageable with each other to lock saidlocking stud to said tubular fitting.

2. A grinding, polishing and feather-edging tool comprising a tubularfitting which is attachable to a drive shaft, a bracket on said tubularfitting, a backing on said bracket, said backing having a hole axiallyaligned with said tubular fitting, a cupped disc having a center cupportion and an annular flange portion which extends outwardly from saidcup portion, said cup portion being disposed within the hole in thebacking, said fiange portion being disposed against said backing toclamp a working disc against said backing, said cup portion having ahole formed therein in concentric relation to the hole in the backing, alocking stud projecting through the hole in the cup portion and the holein the backing and into said tubular fitting, a button portion on theouter end of said locking stud, a compression spring between said buttonand said cup portion to urge said stud outwardly and the cupped discinwardly and against said backing, a locking member on the inner end ofsaid stud and a second locking member on said tubular fitting, saidlocking members being inter-engageable with each other to lock saidlocking stud to said tubular fitting, said locking member comprising alocking spring which is mounted on the outside of said tubular fitting,within the bracket on said fitting, said tubular fitting having anopening formed in its side wall through which a portion of said lockingspring extends for engagement with the locking member on the inner endof the locking stud.

3. A grinding, polishing and feather-edging tool comprising a tubularfitting which is attachable to a drive shaft, a bracket on said tubularfitting, a backing on said bracket, said backing having a hole axiallyaligned with said tubular fitting, a cupped disc having a center cupportion and an annular flange portion which extends outwardly from saidcup portion, said cup portion being disposed within the hole in thebacking, said flange portion being disposed against said backing toclamp a working disc against said backing, said cup portion having ahole formed. therein in concentric relation to the hole in the backing,a locking stud projecting through the hole in the cup portion and thehole in the backing and into said tubular fitting, a button portion onthe outer end of said locking stud, a compression spring between saidbutton and said cup portion to urge said stud outwardly and the cuppeddisc inwardly and against said backing, a locking member on the innerend of said stud and a second locking member on said tubular fitting,said locking members being inter-engageable with each other to lock saidlocking stud to said tubular fitting, said locking member comprising alocking spring which is mounted on the outside of said tubular fitting,within the bracket on said fitting, said tubular fitting having anopening formed in its side wall through which a portion of said lockingspring extends for engagement with the locking member on the inner endof the locking stud, said inwardly extending portion of said lockingspring being biased relative to the locking stud to enable the lockingmember on the inner end of said locking stud to cam said inwardlyextending portion of the locking spring out of the way when said lockingstud is inserted into said tubular fitting.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date ,620,604: Veit Dec. 9, 1952 2,620,605 I-Iolford Dec. 9, 1952

